I think your best bet would be what another poster said and take it to a mechanic...they can tell you. Just maybe get some opinions on where is a good place to go around where you live. Maybe it's the starter.
Without more info, there's no way to tell. It could be the fuel pump, or a loose wire, or a worn muffler bearing for all we know. You can try swapping out the fuel pump, but if that's not it, you'll have to either try some other part, or just take it to a mechanic and have it fixed by a professional. That might be cheaper in the long run any way.
if it turns over but dont crank id try checking for spark first or replace the fuel filter.. you could always pull the fuel line at carb or thottdle body and give it a crank or two and see if its pumping